Turbo installation is complete. The biggest problem was the oiling system since the resevoir is higher than the turbo. I think I finally solved the problem with an inline ball check valve that I will install just before the turbo oil connection. The valve has about 2 lbs of seat pressure that should stop oil from draining into the turbo at rest.

During test runs on the country road in front of the house, I was able to get it up to about 5300 rpms in 3rd gear with 7lbs of boost before I was going too fast for the street and and my A/F was going over 15. If I can get the fuel mapping right, this should work well.

The shaft was broken on the old turbo and I don't know exactly what caused the failure, so I made changes that could account for multiple reasons. These include a larger turbo and a Blow Off Valve on the plenum. I'm hoping the American made Garrett turbo will solve the Chinese bearing failure if that was the major issue.

Look at the vacuum port at the top of the BOV , when the throttle is chopped the vacuum is applied to the top of the diaphragm and the boost px moves the BOV slide up against the spring and allows the boost to vent to atmosphere.

Will you be putting a bigger air filter on that bike? The restriction from the small filter might not be a problem, the turbo suction can handle that. It is the possibility of high vacuum pulling dirt through the filter.

Will you be putting a bigger air filter on that bike? The restriction from the small filter might not be a problem, the turbo suction can handle that. It is the possibility of high vacuum pulling dirt through the filter.

I want to keep the profile as small as possible since it's sticking right out in the airstream. With the lower HP of the 750cc, every little bit helps. The new filter for this turbo is about the same size and I have always gotten good performance from K&N's.

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